Bertram 31 Repower

[Chris]

Hi all, I’m tossing the idea around of repowering my 1970 31 Bertram Bahia Mar. She currently has Perkins T6.354’s rated at 185hp @ 2800 rpm. I have Hurth HSW630A 2.0:1 transmissions and 1 3/8” shafts with 18×23 nib ram props with a 060 cup.. Speeds are on the slower side but fuel consumption is great. Cruise at 2500 and 16kts. I like the Cummins 210’s and from what I read so far I could get a 20kt cruise which I think is the perfect speed for me. A question or two. Can I keep my current transmissions and shafts? I do realize I may to rework my props or get new ones. Thank you.

Topic

[Chris]

Thank you Tony.

[Tony Athens]

Shafts are good–Props are good–Gears are not– you need ZF68A’s 1.5:1R ( exactly like your gear but a different ratio) will be a perfect match and give you a solid 20-22K cruise in the 2200-2300 RPM range

[Author]

Replies